An On-Skin Visually Monitorable Gel-Matrix Zinc-Ion Battery for Electrically Stimulated Wound Healing

Aqueous zinc-ion batteries (ZIBs) feature intrinsic safety, low cost, and environmental compatibility, making them attractive for untapped cutting-edge applications, such as the biomedicine area. Particularly, wearable medical power sources require stable electrical output, mechanical flexibility, and high biocompatibility. Herein, a stable and flexible gel-matrix aqueous ZIB was designed as an on-skin power source for electrically stimulated wound healing. The elaborately designed graded porous framework hydrogel electrolyte (GPF-HGE) obtains high ionic conductivity (17.19 mS cm^-1) and improved mechanical deformation tolerance (46 kPa and 205 J m^-2) due to the porous framework formed in the solvent exchange process. Its transparency property, combined with an annular ring-shaped electrode that generates an electric field aligned with the endogenous wound electric field, enables direct application to wound sites and real-time visual monitoring. The assembled Zn|GPF-HGE|I₂@AC full cells show superior long-term cycling stability accompanied by slight capacity fading, ensuring a steady energy supply for electrical stimulation (ES). Benefiting from its robust electrochemical stability and excellent biocompatibility, the obtained ES device can provide reliable electrical signals and promote wound healing through synergistic antibacterial and anti-inflammatory effects. This work highlights the potential of aqueous ZIBs as advanced biomedical power sources beyond conventional energy storage applications.